Electrically driven clock, particularly for batteries



Jan. 12, 1960 w. RICH 2,920,439

ELECTRICALLY DRIVEN CLOCK, PARTICULARLY FOR BATTERIES Filed May 28, 19562 Sheets-Sheet 1 Wa/ier Ric/7 BY Ma 5w A rroQ/vs Vs Jan. 12, 1960 w.RICH 2,920,439

7 I ELECTRICALLY DRIVEN CLOCK, PARTICULARLY FOR BATTERIES Filed May 2a,1956 2 Sheets-Sheet 2 IN V EN TOR.

Walter Rich GLQWJA Q ML Arrow/5% United States Patent ELECTRICALLYDRIVEN CLOCK, PARTICU- LARLY FOR BATTERIES Walter Rich, Boblingen,Germany Application May as, 1956, Serial No. 587,877,

1 Claim. or. 58-28) This invention relates to an electrical horologicalinstrument and refers more particularly to an electrically drivenclockwork, which is particularly suitable for use in conjunction withbatteries.

Electrically driven clockwork mechanisms have to comply with two mainrequirements, namely, they must have a precise drive and they mustconsume the least possible amount of electricity. This last requirementis particularly important for clocks operated by batteries, since theconsumption of electricity determines the life ofthe battery, as well asthe time intervals of service. Clock mechanisms known in prior art havea swinging system which is driven by direct automatically operatedmagnetic impulses, and which is mechanically connected with a steppingdevice. Therefore, a certain amount of power is taken from the swingingsystem for the driving ofthe actual clock mechanism. Since the drivingpower, and consequently the oscillations of the balance wheel due to thedifferent friction conditions in the clockwork are sometimes different,it is not possible to attain with any such construction a precisestepping movement. Furthermore, constructions of this type require latchlocks or the like for the transmission of movements which are diflicultto manufacture, and which are easily damaged. Another drawback is thatthese devices operate quite noisily which is quite detrimental,particularly when they are used as alarm clocks.

An object of the present invention is the provision of a clock whereinthe above-described drawbacks of prior art constructions are effectivelyeliminated.

Other objects of the present invention will become apparent in thecourse of the following specification.

The objects of the present invention may be realized through theprovision of an electrically driven clockwork having a stepping deviceand a swinging system which is located in an automatically-operatedmagnetic field, whereby the stepping mechanism has a rotary magneticallypolarized armature which is located in an alternating magnetic field. Inaccordance with a preferred embodiment of the inventive idea themagnetic fields of the stepping device and of the swinging system aremagnetically coupled and the actuation of the magnetic fields is.carried out by the swinging system through the actuation of electricalcontacts.

Due to the fact that the stepping device and the swinging system aremechanically separated, the clockwork drive has no influence at all uponthe swinging system, so that changes in the load of the entire apparatushave no effect any more upon the precision of movement of the swingingsystem. Thus, one of the basic require-, ments for properly operatinghorological instruments is attained. The use of a magnetic coupling forthe two magnetic fields instead of the mechanical connection known inprior-art, has a further advantage resulting from the fact that in orderto excite the swinging system a certain minimum value of the magneticfield is required, which is used solely to cover the frictional lossmand the like. However, in the present construction the magneticallypolarized armature of the stepping device which is constructed as apermanent magnet from aluminum, nickel, steel, berium ferrite or likemetal, contributes with its magnetism to the strengthening of themagnetic field for the swinging system due to the coupling of the twofields, so that at least the basic losses are not compensated any moreby the battery but by the permanent magnet. This results in asubstantial saving in electrical current, thereby increasing the life ofthe battery. The operation of the two magnetic fields is carried outfrom the swinging system by the actuation of electrical contacts. Thisis possible only if, as already stated, a magnetically polarizedarmature is used at the same time. This is caused by the fact that dueto the small amount of pressure exerted by the contacts the actuation ofthe contacts cannot take place without so-called chattering. If thearmature were not polarized a corresponding turning of the steppingdevice would take place during each engagement of the contacts, so thatthe step-wise movement would not be accurate. On the other hand, whenthe armature is polarized further engagement of the same contacts willnot aifect the armature in any way. A further advantage is that theconstruction of the present invention eliminates pawl locks and similartransmissions so that friction in the entire apparatus and noise in theoperation thereof, are greatly reduced.

The magnetic fields of the stepping device and of the swinging systemare preferably connected magnetically in-parallel. This greatlysimplifies construction problems and the required shape of the magnetshas additional advantageous mechanical properties.

However, a further simplification may be attained by placing thestepping device and the swinging system in the same magnetic field. Toretain the mechanical separation it is then necessary to mount the twodevices upon different rotary axes.

Since the operation of the contacts and their actuation are of greatimportance for the precise stepping operation of the device and for theconsumptionof the current, it is necessary to provide specially suitableconstructions of such contacts. In accordance with the present inventionthis object is attained through the use of two contacts which consist ofrigid contact pieces, and resilient contacting springs, said contactsbeing constructed as rest contacts. Between these contacts is located arotatably mounted intermediate member consisting of an insulatingmaterial and reciprocated by the swinging system, said member openingone contact and closing the other contact during each movement in onedirection. By means of this type of contacts a particularly smoothoperation with uniform contact pressure is attained without so-calledchattering. The closing of the contacts is particularly effective, sincethe parts thereof do not slide relatively to each other, so that nosparks can be formed.

The invention will appear more clearly from the following detaileddescription when taken in connection with the accompanying drawingshowing a preferred embodiment of the inventive idea.

In the drawing:

Figure 1 is a perspective view, partially diagrammatic, showing thebasic mechanisms included in the clock, some parts having been omittedfor clarity;

Figure 2 illustrates a perspective view of the alarm release; and

Figure 3 illustrates a side elevation of the clock, parts beingdifferently disposed from the diagrammatic showing of Figure 1.

The battery driven clock shown in the drawings has a swinging systemwhich comprises a core 1 made of soft iron and firmly connected with ashaft 2 (Fig. 1). The shaft 2 is rotatably supported upon plates 62 and63 (Fig. 3) and carries a disc 64 which serves as a fly wheel tofacilitate the precise operation of the stepping system. A spring 3 hasone end which is firmly connected with the shaft 2. The other end of thespring 3 extends through the hook65 and is firmly connected at 4 to theplate 66. The hook 65 is carried by swingablelever '67, so that theoperative length of the spring- 3 may be shortened or lengthened by'theswinging of the lever, 67.

The core 1 of the swinging system is located in a mag netic field 7produced by an electro-magnet 8.

The stepping system comprises a polarized armature 5 .consisting of, apermanent magnet and keyed upon a shaft 6. The armature 5 is locatedwithin the magnetic field 9 of the magnet 8. In the illustratedconstruction the magnetic fields 7 and 9 are magnetically interconnectedin parallel. In addition to the armature S-the shaft 6 is. also firmlyconnected with a pinion 10 which meshes with a gear 11. The gear 11 iskeyed upon a shaft which is also firmly connected with a pinion 12meshing with the gear 13. The gear 13 is keyed upon the shaft which isfirmly connected with a pinion 14 meshing with a gear 15. The gear 15 iskeyed upon the minute shaft 16 which carries the minute hand 17 of theclock. As shown in Figure 3, the minute shaft 16 is firmly connectedwith a gear 18 which meshes with the gear 19. The gear 19 is connectedwith a pinion 20 which meshes with a gear 21. The gear 21 is firmlyconnected with a cylindrical hour shaft 22 which surrounds the shaft 16and which carries the hour hand 23. Thus it is apparent that thestep-wise movement of the armature 5 is transmitted to the minute hand17 and the hour hand 23.

The movements of the armature 5 are also used to actuate a ringingdevice. For that purpose the minute shaft 16 carries a pinion 24 whichis keyed thereon, and which meshes with a gear 25. The gear 25 is firmlyconnected with a core 26 which is used for winding a spring (not shown)and used to operate the alarm. The spring is situated in the springcasing 27 and is. mounted so that one end thereof is attached to thecore 26 while its free end presses against the casing 27. The device isso constructed that when a predetermined torque is reached the springwill slide in relation to the spring casing 27, so that. the movement ofthe clock will not be. stopped. It is apparent, however, that the springwill be wound and that the power created by this winding of the springwill be transmitted from the spring casing 27 to a gear 28 which isconnected with the. casing 27. The gear 28 meshes with a pinion 29 whichis firmly connected with the gear 30. The gear 30 cooperates with analarm anchor which actuates the bell ringing device 37. I

The alarm actuating device is best shown in Figure 2 of the drawings.The gear 21 carries a forwardly extending projection 31. The spring 32presses the wheel 21 and therefore the projection 31 against a surface33 of a sleeve 34 which is firmly connected with an alarm wheel 35.

When the hour wheel 21 is rotated clockwise the pro jection 31 movesover the surface 33 until it is dropped in a recess 36 provided in thesurface 33 to permit the release of spring 32 and its locking tip 38from the alarm train.

As shown in Figure 1, the soft iron core 1 carries a pin 42 which iseccentrically mounted thereon, and which is in engagement with a pin 43.The pin 43 is carried by an intermediate member 45, which is rotatablymounted upon a shaft 44. The member 45 is located between two resilientcontact springs 46 and 47. The springs 46 and 47 are adapted to engageimmovable contacts 48 and 49. Thus the two pairs of contacts are restcontacts, namely, when they are not affected by the member 45 thecontact 49 is in operative engagement with the contact 47 while thecontact 46 is in operative engagement with the contact 48. Theresilientcontacts 46 and 47'are carried by a support '50 which is mounted uponthe plate 51'. a

The electrical connections of the apparatus comprise a battery 56:having a negative pole and a positive pole 60. A wire 59 connects thecontacts 48 and 49 with the battery 56. The electro-magnet .8 haswindings 52 and 53. One end of the winding 53 is connected by wire 54with the negative pole 'SSof the battery 56. The other end of thewinding 53 is connected by wire '58 with the contact 46. One end of thewinding 52 of the electro-magnet 8 is connected with the wire,5.4. Theother end of the winding 52 is connected by the wire57 with the contact47.

The operation of the deviceis asfollows:

As soon as oneofflthe' windings'52v or 53 is energized by electricalcurrent from the battery, the electromagnet 8 will be magnetized in thepredetermined direction so that the magnetic fields 7 and 9 willbecreated. 'Then the soft iron core 1 will beturned by magnetic forceswithin the magnetic field 7 againsttheaction of the spring 3, so thatits longitudinal axis will be in the direction of the magnetic lines offorces. This movement will be transmitted by the pins 42 and 43 to theintermediate member 45 which will be turned until it engages one of theresilient contacts 46 or- 47 and moves that resilient contact outwardly,thereby interrupting its engagement with the immovable contact 48 or 49.On the other hand, the other resilient contact will be in engagementwith its immovable contact so that the electric current will flowthrough that winding 52 or 53 which was not energized heretofore whilethe winding which was previously energized will be cut off from thebattery. It should be noted that the second pair of contacts closes onlywhen the core 1 has moved into its middle position. Through the force ofthe spring 3 the core 1 will swing beyond this middle position in theopposite direction, with the result that the other pair of contacts willbe energized. Due to this arrangement, the swinging movement of the core1 takes place under the action of the spring 3 and the actuation of the.contents 46, 48 and 47, 49. It is thus apparent that the swinging of themember 45 and the alternating closing and opening of the contacts willresult in alternating magnetic fields 7 and 9.

As already stated, the magnetic field 9 in which the armature 5 islocated, is changed in the same manner as the magnetic field 7. Whilethe core 1 is made of soft iron, the armature 5 is made of a permanentmagnetic material, and consequently when the polesv of the electromagnet8 and of the magnetic field 9 are reversed, the armature 5 is movedfurther to the extent of one tooth 61. This turning of they armature 5is transmitted through the gear drive consisting of the members 10 to 15to the hands 17 and 23 of the clock, so thatthe clock is operated in theusual manner. The lines of forces emerging from the magnetic armature 5are also effective in the magnetic field'7, so that the force isincreased without withdrawing additionalenergy from the battery 56.

As already stated, the effective length of the spring 3'may be varied bythe lever 67 shown in Figure 3. Due to this arrangement the number ofoscillations of. the members 1 and 45 per time unit, as well as the timeperiods during which the-contacts are closed and opened can beeffectively varied, thereby varying the operation of the clock.

The alarm is operated in the following manner: When the projection 31shownin Figure 2 engages the recess 36 upon the contact surface 33, thewheel 21 will be shifted along with the shaft 22 by the pressure of thespring 32. This shifting takes place in the axial direction toward thewheel 35 to the extent of the length of the projection 31. Due to thismovement the hook-shaped end of the spring 38 will release the lever 39,so that the alarm device 37 can be actuated.

The setting. of the alarm is carried out. by moving the alarm wheel'35counter-clockwise by a shaft, and pinion whichare not shown in thedrawings. This movement of thewheel 35 determines the length of the pathof the projection 31- upon the surface 33 until it reaches the recess3,6;

The spring 41' (Fig. 3) presses against thegear. 15 whichis, firmlyconnected with. the pinion 24,. so that due to the frictional engagementbetween the spring 41 and the gear wheel 15, the minute shaft 16 can beset without influencing the rest of the mechanism. 3

It is apparent that the example shown above has been given solely by wayof illustration and not by way of limitation, and that it is capable ofmany variations and modifications within the scope of the presentinvention. For example, the two magnetic fields may be combined into asingle field. All such variations and modifications are to be includedwithin the scope of the present invention.

What is claimed is:

A battery driven horological instrument, comprising means producingmagnetic fields, a contact-making and breaking device operativelyconnected with said means and reversing the direction of said magneticfields, a swinging element located in the magnetic field and swingablewhen the magnetic field is reversed, said swinging element beingoperatively connected with said contact-making and breaking device toreverse the direction of the magnetic fields during each swingingmovement of the swinging element, a magnetically polarized rotaryarmature located in the magnetic field, and a clockwork operativelyconnected with said armature.

References Cited in the file of this patent UNITED STATES PATENTS343,976 Lange June 15, 1886 1,167,762 Kettering Ian. 11, 1916 1,907,919Whitehead May 9, 1933 1,914,231 Armstrong June 13, 1933 2,150,516Minneker Mar. 14, 1939 2,768,495 Sullivan Oct. 30, 1956 FOREIGN PATENTS7,701 Great Britain Apr. 2, 1903 611,450 France July 5, 1926 1,092,411France Nov. 10, 1954 290,656 Switzerland Aug. 1, 1953

